1. Field of the Invention
The present invention relates to internal supply voltage generation, and more particularly, to a semiconductor memory device for independently controlling internal supply voltages, and a method of using the same.
2. Description of the Related Art
As semiconductor memory devices have become faster and more highly integrated, an internal supply voltage generating circuit has been employed to reduce an operating current. That is, an internal supply voltage generating circuit receives an internal reference voltage, and generates an internal supply voltage from an external voltage. An exemplary supply voltage generating circuit for generating internal supply voltages is disclosed in U.S. Pat. No. 6,087,891.
An internal boosting voltage is obtained by boosting an internal supply voltage provided from the internal supply voltage generating circuit. For example, in Dynamic Random Access Memories (DRAMs), the internal boosting voltage is used to ensure a stable word line voltage. Also, the internal boosting voltage is used in split gate circuits which separate a cell array from a sense amplifier circuit, row driver circuits of DRAM or SRAM, or clock driver circuits, etc.
In conventional technologies, the internal boosting voltage and the internal supply voltage (that is, an array voltage) which is supplied to the memory cell array depend on the internal reference voltage. That is, as the internal reference voltage increases or decreases, the internal boosting voltage and the array voltage are also increased or decreased. Also, since the internal boosting voltage is controlled by a predetermined gain in an internal boosting voltage generating unit, it is difficult to independently control the internal boosting voltage and the array voltage. That is, according to conventional technologies, it is impossible to independently control the internal boosting voltage and an array voltage.